Cutting tool



Sept. 5, 1944. w. T. BRADLEY CUTTING TOOL 2 Sheets-Sheet i Filed Aug. 9, 1943 YINVENTOR. MK! 7.- BY

Sept. 5, 1944.

w. T. BRADLEY CUTTING TOOL Filed Aug. 9 1943 2 Sheets-Sheet 2 IN VEN TOR.

W/ZZ/fl/f 77 584045). BY

Patented Sept. 1944 UNITED :PATENT CUTTING TOOL 'l williarn T.. Bradley, St. LouisgMich. Application August 9, 194},- Serial N0.-49 7,948 Z 8..Clai ms. (Cl. 341F329) This invention" relates to cutting tools and more particularly to those especially adapted for cutting and grooving fibrousmaterials, such as composition board.

The principal object of the invention istoprovide a convenient tool of the character described adapted to hold -any;one of anumber of interchangeable unitary'bl-ade holders formaking different typesof cuts; in composition boards and the like.

Another object of the invention is to provide such atoolof extrem'elysirnple and economical construction.

A still-further-eblject isto provide a novel form of latch for releasably holding any one of anumher of unitary blade holder inthe cutting tool whereby the different bladeholders; may be quickly interchanged with each other.

A still furtherobject is to-provide a tool of the 'character'described in which ablade holder is firmlylocated againstmovement relative to the mainbodyof-the cuttin tool.

- These objects-will more fullyappearinthe following specification when read in connection-with the accompanying-drawings; wherein t V Figure 1' is a side elevational view of-the main bodyof the too1,- parts--b e ing broken away to more clearlyshow-the'construction thereof;

Figure-2 is abottom plan vieW'of-the main-body of the tool-with-parts broken'away to show-the interiorconstruction thereof Figure 3 is atop-plan vi'ewof one oftheinterchangeable blade holders employed with the tool;

'Figu're 4- is aside elevationalviewbf the-blade holdershown in-Figure-3;

Figure 5 is a sideelevationaLview-of thecomplete tool with the blade-holderof Figures 3-and 4 I in place therein; 7 -Figure 6 a is a cross-sectional View taken on substantially-the line 6-6 of Figure 5;-and

Figures 7 and B-areside-elevational and bottom plan views respectively of ;anothertype of blade holder foruseWith-the tool.

Referring now to the drawings-in more detail,

- the invention-comprises generally amainbody portion 1 0,--releasab1e--latching means designated in its entiretybythenumeral--l l-,- and a releasable blade holder, --such as that shown in Figures 3 and 4 or in-Figures Land 8.

The main-body portion --I0- of the --too1 is an elongated blockoigenerally-rectangular.cross section-having a flat-bottom-work engagingsurface l2.- The -body portion lflmay-be -of any *suitable'material; but preferably it is formedof wood or molded l plastic=material. .Between: the ends oftheblock: and extending upwardly, from the bottom surface thereofsis a .recess. |3.' The recess-extends iromlsidetoside of the .block, a.nd

is of generallyrectangular configuration gAt one side of the recess is a V-shaped groove M which extends fromthebottom' surface 12 to the top 0-1;"!

V the recess 1 3.- The upright cornersof the recess ;l3-on one side thereof are beveled to provide shouldersthe purposeof {which-Will presently appear.

= A- cylindrical 'ho1e l6' extends from-the end of the block opposite the; groove I ithroug'hthe ad- -jacent wal-Lbffthe recess. -The hole |6-receives a V plunger ll having a conical tip I8 and a shank-l9 of somewhatreduced diameter. Thelargerend 10 of the plunger isslidablyfitted in the holeJB and substantially fills the same. Acoiled spring22ll surrounds thereduced shankl Sand is positioned -in-the hole l6 -back ofthe enlarged .portio-n'oi -theplungerl'l,

5 A-metalguide .ZLof -angular cross-section is secured t0-13he-end of the blockthatcarristhe plunger-l1. :tOne leg.2 la oftheangular guide ..2I

is secured-in avertical position. to the .end..of -the b-lock thatztheplungerv I1. is .locatedin. .The

leg- 21a is provided withan openingof substantially the same diameterias .the .reduced. section ,..-l9 of the plungenlB. 1;.The..opening.- isycoaxially maligned with holexilB and .the;..plunger..extends throughthat opening vIIhe coiled springiz i1 thus abutsthe uprightleg .Zla of the guide 2|v and is 1 .held incompressed position thereby, so. as to force lthe. plunger in a direction toward the recess1l3.

'The horizontal leglzlb of the; guide His-proovided with asrectangular/ notch 22 receiving one 0 arm of an angular lever .orhandler2 3. That arm of the. lever. is ,pivotally connected to the outer end of. the :plunger l1 and prevents the plunger lfrom. being. forced. completely outv of the hole ;I 6 intothe recessrl3 lby thegspringifl. The other 5 .armof..the lever-:23 isadapted ,to. be engaged by anthehandofsthe operator toretract; the plunger .IL, .ln retractingthe plunger. thelever is forced from its normal.positi0n,1:ShoWn.in.(1012 2 1 li to the fulleline position shown;1n -;Figure landjn 0 so doing. it fulcrums; about the bottom of; the

groove- I 4- in onewside of the recess. I3.. A pair of outwardly extending inclined- -shouldersQ25 fit v against the shoulders l5'at one sideoi the recess. At the end'of theblock 3l opposite the tongue-24 is a conical recess 26 adapted to receivethec0n- .55 vical tip 18 of the plunger I'I.

Theblock 3|. is, provided with a'notchfl (see Figure 6) extending infrom'onefside thereof, the bottom of which is inclined' A zcuttingjfrblade,

which maybe a common razorbladeli8 v is. laid flat on the inclined surface with its Iouttingedge extending below the bottom surface of the blade holder, as indicated in Figure 4. The blade is The guide 32 is notched out at 33 and the edges of the notch are beveled as at 34 to permit shavings to leave the notch 21 in the block 3| and prevent the tool from clogging. The guide extends a considerable distance below the bottom" of the blade holder and below the bottom of the main body portion when the blade holder is in place. The guide is adapted to be positioned against an upright edge of a board to hold the cutting blade in proper position relative to the work as the tool is traversed along thework.

The blade holder is positioned in the body portion in the manner disclosed in Figure 5 with the guide 32 extending a substantial distance below the main body portion. The blade holder is placed in the body portion by retracting the plunger I! and pushing the blade holder upwardly into the recess so that the tongue 24 and shoulders 25 engage the groove I4 and shoulders the same, and releasable latch means on said IS on the body portion. The top surface of the blade holder, of course, fits flush against the top of the recess I3. The plunger is then released and the spring 20 forces the plunger l1 into the recess 26 in the end of the blade holder. The latter is thus securely latched in place.

Another form of blade holder and its cutting blade is shown in Figures 7 and 8. This blade holder is primarily for the purpose of severing a board of composition material or the like into two parts. The blade holder is composed of two identical blocks 4| and 42. The two blocks are secured together by means of transverse screws '43 and carry between them a razor blade or other cutting blade 44. Preferably the cutting blade is inclined as shown in Figure 'l. The two blocks 41 and 42 when assembled together fit closely within the recess 13 in the body portion of the tool. The blocks are provided with tongues 45 which fit in the groove I4 and are also formed to provide a conical recess 46 to receive thetip of the plunger ll. This blade holder is positioned in and released from the body portion of the tool in the same manner as the previous device. It is not furnished with a guide, such as the guide 39, because the cutting blade is normally used at a considerable distance from an edge of the-work and some other form of guide must be em-, ployed.

From the foregoing it will be seen that this invention provides a simple, convenient and economical tool for making various types of cuts in composition boards and the like. The variety of cutting blades and tool holders employed'is practically unlimited, though only two have been shown for purposes of illustration. A wide variety of tools which take up little space and are relatively light in weight may be carried about and yet so rapidly interchanged with each other as to make them practically one tool. This eliminates the need for providing a number of relatively large and cumbersome tools for the different requirements.

The manner of locking the blade holders in the main body portion is positive in action yet provides for instant release of the blade holders when desired.

The scope of the invention is indicated in the appended claims.

body portion for releasably securing said blade holder in said recess.

2. A cutting tool of the character described comprising a hand engaging body portion having a work engaging bottom surface and a non-circular recess extending upwardly from said bottom surface, a unitary blade holder mounted in said recess, said blade holder being of substantially the same shape as said recess wherebyto prevent turning movement of said blade holder in said recess, and releasable latch means on said body portion for releasably securing said blade holder in said recess.

3. A cutting tool of the character described comprising a hand engaging body portion having a work engaging bottom surface and a generally rectangular recess extending upwardly into said body portion from said bottom surface, a unitary blade holder positioned in said recess, said blade holder and the walls of said recess being formed to provide cooperating interlocking means preventing, relative lateral movement of said blade holder and body portion, and releasable latching means on said body portion engaging said blade holder for preventing relative vertical movement of said blade holder and body portion.

g 4. A cutting tool of the character described comprising a hand engaging body portion having a work engaging bottom surface and a recess extending upwardly from said bottom surface, a unitary blade holder removably mounted in said recess, a cutting blade fixedly connected to said blade holderand removable therewith, said blade holder and body portion having cooperating interlocking means thereon for preventing lateral and longitudinal movement of said blade holder relative to said body portion, and releasable latch means on said body portion engaging said blade holder for releasably latching the latter in said recess.

- 5. A cutting toolof the character defined in claim 4 wherein said latch means comprises a spring pressed plunger slidable in said body portion and engageable in a recess in said blade holder. I

6. A cutting tool of the character defined in claim 4wherein said latching means comprises a spring pressed plunger slidable in said body portion and a lever pivotally attached to said plunger for retracting said plunger to release said blade holder. v

'7. A cutting tool of the character defined in claim 4 wherein said blade holder is provided with rigid guide means for engaging an edge of the work, said guide means extending at right angles to the bottom surface of the tool.

8. A cutting tool of the character described comprising a hand engaging body portion having a bottom work engaging surface and an upwardly extending non-circular recess therein, a uni- V tary blade holder mounted infsaid recess, said H WILLIAM T. BRADLEY. 

